This application claims the priority of Korean Patent Application No. 2005-27620, filed on Apr. 1, 2005, in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.
1. Field of the Invention
The present invention relates to a switched reluctance (SR) generator and, more particularly, to an SR generator with improved generation capability in a low-speed range.
2. Description of Related Art
An SR generator is an energy conversion device which, through electronic switching, applies electrical energy from a voltage source to a winding having at least one phase over a prescribed range of rotor angle and receives back from the phase winding over a later range of rotor angle a larger quantity of energy than previously applied. This additional energy is mechanical energy, imparted to the generator rotor by applying a torque in the direction of rotation. Such an SR generator is advantageous in that it can generate energy in a low-speed range since it outputs in a form of a current source.
Conventionally, induction generators or synchronous generators have been used as wind generators. The induction generator is simple in structure and is inexpensive, while there are disadvantages in that it needs an additional gear box to keep a constant speed upon generating electricity and a speed range of wind necessary to generate electricity is limited. Meanwhile, there are disadvantages in that the synchronous generator is complex in structure and is expensive. In addition, in the synchronous generator, a battery is not charged at low wind speeds since voltage outputted from the generator is small. Accordingly, it is very difficult to generate electricity using the induction generators or synchronous generators in an area where the wind speed is low, such as in Korea. While developing a generator that is able to efficiently generate electricity by wind power even in a low-speed range, the present inventor has found it possible to improve the SR generator to be applied to such an area.